Washington: A small drone known as a "quad copter" crashed on the grounds of the White House in the early hours of Monday but the drone did not appear to be dangerous, a White House spokesman said.

A government employee told the US Secret Service that he was flying the unmanned aircraft recreationally before he lost control and accidentally breached the secure perimeter of the presidential mansion, The New York Times reported.

The US Secret Service, the agency responsible for protecting the president, his family and the White House, did not confirm that anyone had admitted to flying the drone.

The device, approximately two feet (61 cm) in diameter, was spotted flying at a low altitude at 3:08 am EST (0808 GMT) before it crashed on the southeast side of White House grounds, Secret Service spokeswoman Nicole Mainor said in a statement.

"An investigation is underway to determine the origin of this commercially available device, motive, and to identify suspects," Mainor said.

White House spokesman Josh Earnest told reporters traveling with President Barack Obama in India that "the early indications are that it does not pose any sort of ongoing threat right now to anybody at the White House."

Obama is in New Delhi for three days to forge closer ties with India, part of a strategy to "rebalance" US defense and trade to Asia to counter a more assertive China.

His wife, Michelle Obama, accompanied the president. Their daughters, Sasha and Malia, and their grandmother, Michelle Robinson, stayed behind.

"I don`t have any reason to think at this point that the first family is in any danger," Earnest said.

US regulators are working to draft new rules for commercial drones used for farming and news gathering. The small remote-controlled aircraft also have become popular as toys, raising privacy concerns and safety issues after close calls with jets.

The Secret Service also has come under scrutiny after several incidents involving White House security. Its director resigned in October, and an independent review concluded that it needs to build a better fence and hire more officers.

Mainor said there was an "immediate alert and lockdown of the complex until the device was examined and cleared."